WebClient.UploadValuesTaskAsync Method (Uri, String, NameValueCollection)
Uploads the specified name/value collection to the resource identified by the specified URI as an asynchronous operation using a task object.
Assembly: System (in System.dll)
[ComVisibleAttribute(false)] [HostProtectionAttribute(SecurityAction.LinkDemand, ExternalThreading = true)] public Task<byte> UploadValuesTaskAsync( Uri address, string method, NameValueCollection data )
- Type: System.Uri
The URI of the resource to receive the collection.
- Type: System.String
The HTTP method used to send the collection to the resource. If null, the default is POST for http and STOR for ftp.
- Type: System.Collections.Specialized.NameValueCollection
The NameValueCollection to send to the resource.
The address parameter is null.
The data parameter is null.
The URI formed by combining BaseAddress, and address is invalid.
method cannot be used to send content.
There was no response from the server hosting the resource.
An error occurred while opening the stream.
The Content-type header is not null or "application/x-www-form-urlencoded".
This operation will not block. The returned Task<TResult> object will complete after the name/value collection has been uploaded to the resource. The name/value collection is sent asynchronously using thread resources that are automatically allocated from the thread pool.
Asynchronous operations that have not completed can be canceled using the CancelAsync method.
If the underlying request is not understood by the server, the underlying protocol classes determine what occurs. Typically, a WebException is thrown with the Status property set to indicate the error.
If the Content-type header is null, this method sets it to "application/x-www-form-urlencoded".
If the BaseAddress property is not an empty string ("") and address does not contain an absolute URI, address must be a relative URI that is combined with BaseAddress to form the absolute URI of the requested data. If the QueryString property is not an empty string, it is appended to address.
This method uses the STOR command to upload an FTP resource. For an HTTP resource, the POST method is used.
This member outputs trace information when you enable network tracing in your application. For more information, see Network Tracing.
The HostProtectionAttribute attribute applied to this type or member has the following Resources property value: ExternalThreading. The HostProtectionAttribute does not affect desktop applications (which are typically started by double-clicking an icon, typing a command, or entering a URL in a browser). For more information, see the HostProtectionAttribute class or SQL Server Programming and Host Protection Attributes.
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.